Among known supporting devices of this type there is known one which supports a table for use in a conference or the like. The device supports the conference table with a supporter for transport such as casters or sliders, which are associated with a locking mechanism so designed as to put the supporter into a movable condition in which the casters or sliders can rotate or slide and alternatively into a restrained condition in which the movement thereof is locked.
There is known another device which is provided with a supporter for restraint such as adjusters along with the above-mentioned casters or sliders as a supporter for transport, the two kinds of supporters being so arranged by a changing mechanism that one of them is vertically movable relative to the other between a movable position in which only the casters contact the floor and a retracted position in which both the casters and the adjusters simultaneously contact the floor.
With the locking mechanism, however, there arises a problem that since the locking mechanism is provided on the casters or sliders themselves, in order to operate the mechanism the operator must crouch down adjacent the base of the table that is the object being supported, so that the operability of the mechanism is very low. The structure of the changing mechanism must be such that the mechanism is ganged with an operating lever provided at a position suitable for an operator to handle it. To provide the operating lever at a position easy for handling, a complex transmission must be interposed therebetween, with resulting increase in the manufacturing steps and cost.
To solve the problem, in the case of, for example, a foldable table which is provided, in addition to the above-mentioned first changing mechanism, with a second changing mechanism such as a flapping mechanism which is placed in a position for use and alternatively in a position for nonuse, the operation of the second changing mechanism is transferred to the first changing mechanism to operate the same so as to make it unnecessary to operate the first changing mechanism individually.
With this arrangement, however, when the table top is placed in the position for use, the table as a whole has already been fixed so that in order to move the table the table top must be returned to the position for nonuse. Therefore, if many tables are to be arranged side-by-side with their top plates contacting each other in edge-to-edge relation, it is impossible to arrange them with their tops kept in the position for use, so that the working efficiency of arranging the tables is very low. Moreover, the table top must be kept in the position for use in order to keep the table immovable for storage, so that it is difficult to store many tables stably in the unused condition with their tops kept upright in face-to-face relation.